Oil prices dipped overnight ahead of a meeting of the world's biggest exporters, who will discuss cutting output to help shore up prices and curb excess supply.

The Organisation of the Petroleum Exporting Countries, Russia and other producers will meet in Vienna this week to discuss a potential cut in production.

A monitoring committee of OPEC and its allies, including Russia, agreed on the need to cut oil output in 2019, two sources familiar with the discussions said, adding that volumes and the baseline for cuts were being debated.

Brent crude futures fell 52 cents to settle at $US61.56 a barrel after earlier reaching a session high of $US63.29 a barrel and a low of $US60.80.

U.S. West Texas Intermediate crude futures fell 36 cents to settle at $US52.89 a barrel.

The contract traded between $US54.44 a barrel and $US52.16 a barrel during the session.

Russian Energy Minister Alexander Novak told reporters he had a "good" meeting with his Saudi counterpart, Khalid al-Falih, on Wednesday and they planned more talks.

"All of us, including Russia, agreed there is a need for a reduction," Oman's Oil Minister Mohammed bin Hamad Al-Rumhy told reporters after a ministerial committee that groups Saudi Arabia, Russia and several other producers met on Wednesday.

Russia's number two oil producer Lukoil is ready to cut oil production if OPEC and other leading producers agree to do so, though it would be technically difficult in winter, RIA news agency quoted the company's head Vagit Alekperov as saying.

OPEC wants to avert a buildup in global oil inventories like the one that sent prices from late 2014 into a prolonged slump that brought Brent to below $US30 a barrel at the start of 2016.

US President Donald Trump pressured OPEC not to reduce output.

"Hopefully OPEC will be keeping oil flows as is, not restricted. The World does not want to see, or need, higher oil prices!" Trump wrote on Twitter on Wednesday.

"None of today's comments should have come as a surprise since the key unknown remains the size of any such reduction and how the cuts are distributed," Jim Ritterbusch, president of Ritterbusch and Associates, said in a note.

"The Trump administration appears to be maintaining pressure on the Saudis to limit any production cuts in precluding significant price advances from current levels.

"And the fact that Russia still appears somewhat non-committal would appear to tilt odds in favour of about a 1 to 1.1 million barrels per day reduction."

Saudi Arabian crude supply in November rose to 11.3 million barrels per day, a source familiar with the matter said.

That marks a rise from October's 10.65 million bpd.

US crude inventories rose by 5.4 million barrels in the week to November 30 to 448 million, data from industry group the American Petroleum Institute showed on Tuesday.

Official US government inventory data is due on Thursday, delayed by one day.